Pick up truck piggy back unit



FIG. 1 is a top plan view of the novel pick up truck piggy back unit;

FIG. 2 is a side (either) elevational view thereof, the other side view being a mirror image thereof;

FIG. 3 is a bottom plan thereof;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is a perspective view thereof.

The broken line showing of environment is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a pick up truck piggy back unit, as shown and described. 